Carbon dioxide (CO2) is a naturally occurring substance in most hydrocarbon subterranean formations. Carbon dioxide also may be used for recovering or extracting oil and hydrocarbons from subterranean formations. One carbon dioxide based recovery process involves injecting carbon dioxide into an injection well, and recovering heavy hydrocarbons and perhaps some of the carbon dioxide from at least one recovery well. Carbon dioxide reinjection process also may produce natural gas liquids (NGLs).